Question 15·Hard·Transitions
The gene-editing tool CRISPR-Cas9 can be devastatingly precise, cutting DNA strands at locations specified by researchers. That precision, ____ , is exactly what worries bioethicists, who fear that errors may go unnoticed until they are passed on to future generations.
Which choice completes the text with the most logical transition?
For transition questions, first ignore the answer choices and read the sentences together to decide what the logical relationship is: addition, contrast, cause-effect, example, or something unexpected. Then, test each choice by its usual function (e.g., "therefore" = cause-effect, "meanwhile" = same time, etc.) and eliminate any that don’t match that relationship in context. Always make sure the transition fits both the meaning and the tone of the combined sentences, not just one part.
Hints
Check the direction of the relationship
Ask yourself: Does the second sentence support the first, explain a result of it, contrast with it, or just describe something happening at the same time?
Focus on the phrase "is exactly what worries bioethicists"
Is the precision being presented as a straightforward benefit, or is there something surprising about the fact that this supposedly good feature is causing worry?
Match the meaning of each transition to the relationship
Think about what each word usually signals: similar ideas, cause-and-effect, time, or an unexpected twist—then see which best fits how precision relates to the bioethicists’ concern.
Step-by-step Explanation
Understand what the first sentence is saying
The first sentence tells us that CRISPR-Cas9 is devastatingly precise and can cut DNA exactly where researchers choose. This sounds like a powerful and generally positive capability.
Understand what the second sentence is saying
The second sentence says: That precision ... is exactly what worries bioethicists, who fear that errors may go unnoticed until they are passed on to future generations. So the very thing that seems good (precision) is also a source of concern (because tiny errors might be hidden and then inherited).
Identify the relationship between the two ideas
The relationship is not simple cause-and-effect in a straightforward way, nor is it just "also" or "at the same time." Instead, there's a twist: we would expect precision to be reassuring, but here it is worrying—an unexpected or ironic outcome.
Match each transition to the relationship
Now test each option:
- "correspondingly" means in a similar way/as a matching result, which does not show a surprising twist.
- "therefore" signals a straightforward cause-and-effect conclusion.
- "meanwhile" marks something happening at the same time, a time/contrast marker.
- One option signals that the result is surprising or opposite to what we’d normally expect, which fits the idea that precision—usually good—is the problem. The word that shows this unexpected, ironic contrast is “ironically.”